DESCRIPTION

This module creates global pseudovariables which format dates and times, according to formatting codes you pass to them in strings.

The %time formatting codes are designed to be easy to remember and use, and to take up just as many characters as the output time value whenever possible. For example, the four-digit year code is "yyyy", the three-letter month abbreviation is "Mon".

The nice thing about having a variable-like interface instead of function calls is that the values can be used inside of strings (as well as outside of strings in ordinary expressions). Dates are frequently used within strings (log messages, output, data records, etc.), so having the ability to interpolate them directly is handy.

Perl allows arbitrary expressions within curly braces of a hash, even when that hash is being interpolated into a string. This allows you to do computations on the fly while formatting times and inserting them into strings. See the "yesterday" example above.

The format strings are designed with programmers in mind. What do you need most frequently? 4-digit year, month, day, 24-based hour, minute, second -- usually with leading zeroes. These six are the easiest formats to use and remember in Time::Format: yyyy, mm, dd, hh, mm, ss. Variants on these formats follow a simple and consistent formula. This module is for everyone who is weary of trying to remember strftime(3)'s arcane codes, or of endlessly writing $t[4]++; $t[5]+=1900 as you manually format times or dates.

Note that mm (and related codes) are used both for months and minutes. This is a feature. %time resolves the ambiguity by examining other nearby formatting codes. If it's in the context of a year or a day, "month" is assumed. If in the context of an hour or a second, "minute" is assumed.

The format strings are not meant to encompass every date/time need ever conceived. But how often do you need the day of the year (strftime's %j) or the week number (strftime's %W)?

For capabilities that %time does not provide, %strftime provides an interface to POSIX's strftime, and %manip provides an interface to the Date::Manip module's UnixDate function.

If the companion module Time::Format_XS is also installed, Time::Format will detect and use it. This will result in a significant speed increase for %time and time_format.

VARIABLES

time

$time{$format}
$time{$format,$time_value};

Formats a unix time number (seconds since the epoch), DateTime object, stringified DateTime, Date::Manip string, or ISO-8601 string, according to the specified format. If the time expression is omitted, the current time is used. The format string may contain any of the following:

Millisecond and microsecond require Time::HiRes, otherwise they'll always be zero. Timezone requires POSIX, otherwise it'll be the empty string. The second codes (s, ss, ?s) can be 60 or 61 in rare circumstances (leap seconds, if your system supports such).

Anything in the format string other than the above patterns is left intact. Any character preceded by a backslash is left alone and not used for any part of a format code. See the "QUOTING" section for more details.

For the most part, each of the above formatting codes takes up as much space as the output string it generates. The exceptions are the codes whose output is variable length: Weekday, Month, time zone, and the single-character codes.

The mixed-case "Month", "Mon", "Weekday", and "Day" codes return the name of the month or weekday in the preferred case representation for the locale currently in effect. Thus in an English-speaking locale, the seventh month would be "July" (uppercase first letter, lowercase rest); while in a French-speaking locale, it would be "juillet" (all lowercase). See the "QUOTING" section for ways to control the case of month/weekday names.

Note that the "mm", "m", and "?m" formats are ambiguous. %time tries to guess whether you meant "month" or "minute" based on nearby characters in the format string. Thus, a format of "yyyy/mm/dd hh:mm:ss" is correctly parsed as "year month day, hour minute second". If %time cannot determine whether you meant "month" or "minute", it leaves the mm, m, or ?m untranslated. To remove the ambiguity, you can use the following codes:

For those who prefer strftime's weird % formats, or who need POSIX compliance, or who need week numbers or other features %time does not provide.

manip

$manip{$format};
$manip{$format,$when};

Provides an interface to the Date::Manip module's UnixDate function. This function is rather slow, but can parse a very wide variety of date input. See the Date::Manip module for details about the inputs accepted.

If you want to use the %time codes, but need the input flexibility of %manip, you can use Date::Manip's ParseDate function:

print "$time{'yyyymmdd', ParseDate('last sunday')}";

FUNCTIONS

time_format

time_format($format);
time_format($format, $unix_time);

This is a function interface to %time. It accepts the same formatting codes and everything. This is provided for people who want their function calls to look like function calls, not hashes. :-) The following two are equivalent:

This is a function interface to %strftime. It simply calls POSIX::strftime, but it does provide a bit of an advantage over calling strftime directly, in that you can pass the time as a unix time (seconds since the epoch), or omit it in order to get the current time.

time_manip

manip($format);
manip($format,$when);

This is a function interface to %manip. It calls Date::Manip::UnixDate under the hood. It does not provide much of an advantage over calling UnixDate directly, except that you can omit the $when parameter in order to get the current time.

QUOTING

This section applies to the format strings used by %time and time_format only.

Sometimes it is necessary to suppress expansion of some format characters in a format string. For example:

$time{'Hour: hh; Minute: mm{in}; Second: ss'};

In the above expression, the "H" in "Hour" would be expanded, as would the "d" in "Second". The result would be something like:

8our: 08; Minute: 10; Secon17: 30

It would not be a good solution to break the above statement out into three calls to %time:

"Hour: $time{hh}; Minute: $time{'mm{in}'}; Second: $time{ss}"

because the time could change from one call to the next, which would be a problem when the numbers roll over (for example, a split second after 7:59:59).

For this reason, you can escape individual format codes with a backslash:

$time{'\Hour: hh; Minute: mm{in}; Secon\d: ss'};

Note that with double-quoted (and qq//) strings, the backslash must be doubled, because Perl first interpolates the string:

$time{"\\Hour: hh; Minute: mm{in}; Secon\\d: ss"};

For added convenience, Time::Format simulates Perl's built-in \Q and \E inline quoting operators. Anything in a string between a \Q and \E will not be interpolated as any part of any formatting code:

$time{'\QHour:\E hh; \QMinute:\E mm{in}; \QSecond:\E ss'};

Again, within interpolated strings, the backslash must be doubled, or else Perl will interpret and remove the \Q...\E sequence before Time::Format gets it:

$time{"\\QHour:\\E hh; \\QMinute:\\E mm{in}; \\QSecond\\E: ss"};

Time::Format also recognizes and simulates the \U, \L, \u, and \l sequences. This is really only useful for finer control of the Month, Mon, Weekday, and Day formats. For example, in some locales, the month names are all-lowercase by convention. At the start of a sentence, you may want to ensure that the first character is uppercase:

$time{'\uMonth \Qis the finest month of all.'};

Again, be sure to use \Q, and be sure to double the backslashes in interpolated strings, otherwise you'll get something ugly like:

BUGS

The format string used by %time must not have $; as a substring anywhere. $; (by default, ASCII character 28, or 1C hex) is used to separate values passed to the tied hash, and thus Time::Format will interpret your format string to be two or more arguments if it contains $;. The time_format function does not have this limitation.

REQUIREMENTS

Time::Local
I18N::Langinfo, if you want non-English locales to work.
POSIX, if you choose to use %strftime or want the C<tz> format to work.
Time::HiRes, if you want the C<mmm> and C<uuuuuu> time formats to work.
Date::Manip, if you choose to use %manip.
Time::Format_XS is optional but will make C<%time> and C<time_format>
much faster. The version of Time::Format_XS installed must match
the version of Time::Format installed; otherwise Time::Format will
not use it (and will issue a warning).

AUTHOR / COPYRIGHT

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This module is copyrighted only to ensure proper attribution of authorship and to ensure that it remains available to all. This module is free, open-source software. This module may be freely used for any purpose, commercial, public, or private, provided that proper credit is given, and that no more-restrictive license is applied to derivative (not dependent) works.

Substantial efforts have been made to ensure that this software meets high quality standards; however, no guarantee can be made that there are no undiscovered bugs, and no warranty is made as to suitability to any given use, including merchantability. Should this module cause your house to burn down, your dog to collapse, your heart-lung machine to fail, your spouse to desert you, or George Bush to be re-elected, I can offer only my sincere sympathy and apologies, and promise to endeavor to improve the software.

Module Install Instructions

To install Time::Format, simply copy and paste either of the commands in to your terminal